<template>
  <div class="star" :class="starSize">
    <span class="star-item" v-for="(itemClass,index) in itemClasses" :key="index" :class="itemClass"></span>
  </div>
</template>

<script>
const CLS_LENGTH = 5
const CLS_ON = 'one'
const CLS_HALF = 'half'
const CLS_OFF = 'none'
export default {
  props: {
    score: {
      type: Number
    },
    size: {
      type: Number
    }
  },
  computed: {
    starSize () {
      return 's' + this.size
    },
    itemClasses () {
      let result = []
      let score = Math.floor(this.score * 2) / 2
      let hasDecimal = score % 1 !== 0
      let integer = Math.floor(score)
      for (let i = 0; i < integer; i++) {
        result.push(CLS_ON)
      }
      if (hasDecimal) {
        result.push(CLS_HALF)
      }
      while (result.length < CLS_LENGTH) {
        result.push(CLS_OFF)
      }
      return result
    }
  }
}
</script>

<style lang="scss" scoped>
  @media screen and (-webkit-min-device-pixel-ratio: 2.0) {
    .s24 .half{
      background-image: url('./star24_half@2x.png')
    }
    .s24 .none{
      background-image: url('./star24_off@2x.png')
    }
    .s24 .one{
      background-image: url('./star24_on@2x.png')
    }
    .s36 .half{
      background-image: url('./star36_half@2x.png')
    }
    .s36 .none{
      background-image: url('./star36_off@2x.png')
    }
    .s36 .one{
      background-image: url('./star36_on@2x.png')
    }
    .s48 .half{
      background-image: url('./star48_half@2x.png')
    }
    .s48 .none{
      background-image: url('./star48_off@2x.png')
    }
    .s48 .one{
      background-image: url('./star48_on@2x.png')
    }
  }
  @media screen and (-webkit-min-device-pixel-ratio: 3.0) {
    .s24 .half{
      background-image: url('./star24_half@3x.png')
    }
    .s24 .none{
      background-image: url('./star24_off@3x.png')
    }
    .s24 .one{
      background-image: url('./star24_on@3x.png')
    }
    .s36 .half{
      background-image: url('./star36_half@3x.png')
    }
    .s36 .none{
      background-image: url('./star36_off@3x.png')
    }
    .s36 .one{
      background-image: url('./star36_on@3x.png')
    }
    .s48 .half{
      background-image: url('./star48_half@3x.png')
    }
    .s48 .none{
      background-image: url('./star48_off@3x.png')
    }
    .s48 .one{
      background-image: url('./star48_on@3x.png')
    }
  }
  .star{
    font-size: 0;
    .star-item{
      display: inline-block;
      background-repeat: no-repeat;
    }
    &.s48{
      .star-item{
        width: 20px;
        height: 20px;
        padding-right: 22px;
        background-size: 20px 20px;
        &:last-of-type{
          padding:0;
        }
      }
    }
    &.s36{
      .star-item{
        width: 15px;
        height: 15px;
        padding-right: 6px;
        background-size: 15px 15px;
        &:last-of-type{
          padding:0;
        }
      }
    }
    &.s24{
      .star-item{
        width: 10px;
        height: 10px;
        padding-right: 3px;
        background-size: 10px 10px;
        &:last-of-type{
          padding:0;
        }
      }
    }
  }
</style>
